Soil pipe in or out which is best?!?!

Hello,
Looking for some guidance and experience.

We are about to extend our house and currently the drawings are for the soil pipe to run down the outside of the house. Our neighbors have suggested we have it moved inside (like they have) to maximize the space at the side of the house (we will be a bins width from the fence once built).

When I spoke with our builder he did not seam a big fan of this due to access/noise and potential blockage issues, but want to check that its not just because its more hard work for him.

When I look online all I can see is people wanting to move internal pipes outside... are they really that bad... are they more haste than they are worth just for a little extra space. Do I stick with outside pipes?

All thoughts and experiences welcome

Up to you, but I can safely say I've done more jobs where I've moved stacks from inside thi outside than the other way around. It saves having boxing-in in a room, taking up space, as well as the potential noise issues

Sounds like your neighbours are more concerned with how it looks outside to them than the benefit to you. Like above if it’s inside it has to be boxed and you lose internal space. Run professionally it will look fine outside and easier to maintain for any future problems.

When I worked in a office that had a soil pipe running through it, you could always tell whether a number one or number two was going down the pipe when upstairs flushed the toilet.

You can have a pipe inside.
If the boxing is soundproofed you won't be able to tell when toilet is flushed, unless you put your ear to the box.
Done many times.
Also, for any future rodding access you should leave a rodding point at ground level and possibly add another one above the new roof extension, however I have never been asked to do this by BC.
Future rodding can be done via ground floor and if really necessary by removing thr toilet which takes 3 minutes.

We went through a stage in the 1970's when external stacks were not permitted, before the regs were relaxed again. In all honesty, in the unlikely event a stack blocks, it doesn't make much difference where it is, provided external access is available to clear any blockage. If you require the external width to get bins through etc, then go for internal, otherwise I wouldn't worry about the neighbours and do what's best for you.